Synthesis and Evaluation of the Potential Use of an Electro-Responsive Hydrogel for the Encapsulation of Carbon Dot-Curcumin Nanoplatforms

Curcumin is a polyphenolic compound recently studied as a potential therapeutic agent for cancer treatment. However, this molecule possesses low solubility in water which complicates its direct use in the organism, making it essential to find a drug delivery system to carry this molecule through hydrophilic environments. To achieve this, carbon dots (CDs) with a polar surface were synthesized from citric acid and urea by solvothermal method, followed by the surface functionalization of the CDs via the adsorption of curcumin molecules (CD-Cur). This nanoplatform was encapsulated inside an electro-responsive hydrogel based on dextran and aniline (Dex/HDI/AT), which acts as a vehicle for CD-Cur. To evaluate the improvement of solubility of curcumin, a drug encapsulation test was carried out to compare its encapsulation rate to a molecule of great hydrophilicity, fluorescein. The results of FTIR, UV-Vis spectroscopy and zeta potential tests enabled to identify the composition of CDs and the functionalization of CD-Cur. The composition and structure of Dex/HDI/AT was confirmed by FTIR and SEM. Finally, the drug encapsulation test demonstrated the capacity of CDs to improve the interaction of hydrophobic curcumin molecules with aqueous-based environments such as the one offered by the DEX/HDI/AT hydrogel.